My philosphy is the less equipment the better. When you have to start putting all sorts of **** (and I do mean ****) on your horse, things are just getting complicated and can often lead towards abuse of the tack. If your horse needs a lot of equipment, it is probably best to take a step back and start working on the ground and flat. I am not saying that people who use martingales are in the wrong. The right kind of equipment used the right way is good. But when you start putting on martingales, chains, and harsh bits, and draw reins, and flashes, and studded cavessons, etc. The list goes on and on. It's time to say enough is enough.
Not saying that your horse does, but that is my personal opinion about people (especially around my barn) who just buy tack because it is new or looks nice.
With that being said, I do have a martingale for my horse, but it isn't for him. It is actually for me. I use the martingale for some extra grip because of his HUGE ass jump, even over the tiny ones. But it is soooo lose that it doesn't even affect him. He doesn't even know that it is there. I wear it just so I don't get jumped out of the saddle.
Good luck with your decision. I hope that I helped